Question

A plane electromagnetic wave of frequency 25 MHz travels in free space along x-direction. At a particular point in space and time, electric field $E = 6.3Vm^{- 1}$.The magnitude of magnetic field B at this point is

• A. $1.2 \times 10^{- 6}T$
• B. $1.2 \times 10^{- 8}T$
• C. $2.1 \times 10^{- 6}T$
• D. $2.1 \times 10^{- 8}T$

Answer 1

Answer: (D)

$2.1 \times 10^{- 8}T$

Answer 2

: As, $B = \frac{E}{c} = \frac{6.3}{3 \times 10^{8}} = 2.1 \times 10^{- 8}T$